While the PPPS problem can be solved with the help of oblivious transfer with hidden access control (OT-HAC) which in turn can be built by anonymous identity-based encryption (IBE) with blind key extraction (BKE) protocol, the designs of existing systems are often complicated and the efficiency are not satisfactory. A simple and efficient approach is especially important for $P_2$ since he is playing a helping role in the protocol.
In this paper, we propose efficient BKE protocols, for an anonymous IBE and an anonymous hierarchical IBE attributed to Ducas in CT-RSA '10. Our protocol for IBE is conceptually simpler and more efficient than an existing proposal by Camenisch $\etal$ in PKC '09. Our protocol for HIBE is the first of its kind in the literature to the best of our knowledge. When compared with the OT-HAC system proposed by Camenisch $\etal$ in PKC '11, our protocol is again conceptually simpler, supports predicates defined by vectors from a large-domain instead of bit-vectors, and allows retrieval of multiple items in one invocation. Finally, we demonstrate their practicality by our performance analysis on prototypes implementation.Category / Keywords: Date: received 15 Aug 2011 Contact author: huanglin at ufl edu Available format(s): PDF | BibTeX Citation Version: 20110817:191258 (All versions of this report) Short URL: ia.cr/2011/445 Discussion forum: Show discussion | Start new discussion